The thesis is about the problem of phase unwrapping, where terrain topography is reconstructed from ambiguous phase values. It is shown how to transform the phase unwrapping problem into a minimum cost flow problem. Moreover, for two recent minimum cost flow algorithms and their different variants an experimental evaluation is given. One of these algorithms, the Dual Ascent algorithm, returns the optimal solution and uses spanning trees, while the other one uses a gradient descent method and returns an approximate solution.